Cut-off knife assembly for continuous rewinders



P. ZERNOV Feb. 28, 1961 CUT-OFF KNIFE ASSEMBLY FOR CONTINUOUS REWINDERS3 Sheets-Sheet 1 Filed Sept. 19, 1958 INVENTOR. PETE-z Zane/vow AT'TOENE Y5 Feb. 28, 1961 P. ZERNOV 2,973,153

CUT-OFF KNIFE ASSEMBLY FOR CONTINUOUS REWINDERS Filed Sept. 19, 1958 3Sheets-Sheet 2 IN V EN TOR.

PETER ZEz/vo/ BY A 7' TOENEY CUT-OFF KNIFE ASSEMBLY FOR CONTINUOUSREWINDERS Filed Sept. 19, 1958 P. ZERNOV Feb. 28, 1961 3 Sheets-Sheet 31 N V EN TOR.

1 57752 ZEEN A T TOENEY,

United States Patent() 2,973,158 CUT-OFF KNIFE ASSEMBLY FOR CONTINUOUSREWINDERS Peter Zernov, Milwaukee, Wis., assignor to Mercury EngineeringCorporation, Milwaukee, Wis., a corporation of Wisconsin Filed Sept. 19,1958, Ser. No. 762,054 1 Claim. (Cl. 242-56) This invention relatesgenerally to apparatus for winding a web of material, wherein thecontinuously moving web is transferred from a completed roll to a newroll so that successive rolls of web are formed without interrupting thewinding operation and the web is transferred while in motion from acompleted roll to a new roll. More particularly, the invention relatesto an improved cut-off knife and presser roll assembly for severing theweb and commencing the winding of the web on a new roll.

, Swinging cut-off knives, per se, are well-known in this art whereinwhen one roll has been completed audit is desired to commence a newroll, the knife swings into cutting relationship with the web. It hasbeen proposed in the past to associate various controlling or guidingmeans with the knife to engage the severed web end and direct it about anew core or shaft. The direction in hich the cut-off knife swingsrelative to the new roll, and its proximity therewith affect the mannerin which the new leading edge of the severed web will engage the newcore. However, manufacturing tolerances and the enormity of the partsinvolved limit the proximity to which the knife can bemoved relative tothe rapidlyrotating new roll. Furthermore, the prior art attempts tosever the web and quickly and smoothly cause it to adhere to the newcore, have usually involved a considerable amount of complex mechanismwhich requires frequent attention and adjustment.

' In accordance with the present invention, an improved flying cut-offknife and presser roll mechanism has been provided for a continuousrewinder, in which the presser roll and knife are simultaneously .causedto engage the web to sever the latter and cause it hesive materialcarried on the new roll.

Another more specific aspect of the invention contemplates that thepresser roll and knife are initially moved as a unit to a point closelyadjacent the web. Upon reaching this point, the presser roll is thenshifted into contact with the web and simultaneously with this lattermovement the knife is shifted relative to the roll to sever the web.After the web is built up to a predetermined extent on the new core, theknife and presser rollassenrbly are automatically returned to theiroriginal position.

Another more specific object of the invention is to provide a flyingcut-off knife for a continuous rewinder, which knife has meansassociated therewith for immediately freeing the newly-formed leadingedge from the knife so as to insure that this edge follows the new coreto start a new roll of material.

These and other objects and advantages will appear hereinafter as thisdisclosure progresses, reference being had to the'accompanying drawings,in whichr Figure 1 is a side elevational view of a cut-off knife andpresser roll unit made in accordance with themesent invention and asused with a conventional turnover rewinder;

the auxiliary arms in their swinging movement. A knifeto adhere to henew roll R2.

2,973,158 Patented Feb. 28, 1961 the knife and presser roll immediatelyat the completion of their second phase of movement;

.Figure 4 is a fragmentary view of the knife as shown in Figure 3, buton an enlarged scale;

Figure 5 is a view taken generally from the line 5-5 in Figure 1; m

Figure 6 is a fragmentary view taken generally along the line 6--6 ofFigure 2, but on an enlarged scale; and

Figure 7 is a pneumatic diagram for the various switches and operatingcylinders.

Referring in greater detail to the drawings, the turnover rewinder 10 isof the type shown in my co-pending United States application Serial No.762,646, filed September 22, 1958, issued on January 31, 1961, as PatentNo. 2,969,930, and entitled Continuous Rewinder For Web Material, andreference may be had to that application if a complete description of itis desired. However, it is believed sufficient to say for purposes ofthis disclosure that this two-position rewinder comprises a stand 11, aroll-carrying frame 12 including a centrally disposed shaft 13 rotatablymounted in the sides of the stand and having web roll receiving cores orrolls R1 and R2 rotatably mounted in its end portions, and guide rolls14, 15 mounted on opposite sides of the frame and adjacent the shaft 13.

Each of the rolls R1 and R2 includes a mandrel having mounted thereon aseries of layers A of tape material provided with an adhesive outersurface so that the ten sioned web TW will adhere to the rolls, as willappear. Each of the rolls R1 and R2 has conventional means (not shown)for driving them so that the web continues to be wound upon a roll aslong as it is in position.

With the web secured to roll R1, the frame 12 is rotated in acounter-clockwise direction to the position shown in Figure l and theroll R1 is rotated to wind the desired amount of material therein. Whena sufiiciently .large roll of material is thus formed, the knife andpresser roll unit 17 is brought into operation to sever the web andcause the new leading edge so formed to be pressed into engagement withthe adhesive A carried by In this manner, a new roll is started on rollR2 and the frame then rotated counterclockwise to lower the completedroll to the ground where it may be readily removed from the frame. A newroll is then placed in the frame and the procedure above mentioned isrepeated to effect a continuous rewinding operation.

A tensioning material supply means 20 is provided adjacent the rewinderand includes a roller 21 mounted between the side walls 22, 23 and underwhich roller the web TW passes as it leaves this supply means.

In accordance with the present invention, a flying cutoff knife andpresser roll assembly 17 is mounted adjacent the upper end of the supplymeans 20, for swinging from the uppermost or inoperative position shownin Figure 1, to the preset or initial position shown in Figure 2, andthen to the operative or cutting position of Figure 3, from which it islater returned to the starting or inoperative position of Figure l.

The assembly 17 includes arms 24, 25 pivoted ontheir respective stubshafts 26 and 27 that are carried in the side Walls 22, 23. Auxiliaryarms 28, 29 are pivotally mounted at one of their ends on the shaft 30which extends between the free ends of arms 24 and 25. Guide blocks 31(Fig. 6) are secured to shaft 30 for guiding supporting bar 32 issecured between the free ends of the auxiliary arms by cap bolts 33 andpins 34.

The knife 35 is held securely against the front edge of bar 32 by thebackup bar 36 and cap bolts 37, the latter of which extend through boththe bar 36 and the knife and are threadably engaged in the bar 32. Asbest shown in Figure 5, the knife has a series of inclined steps, theleading edge of each of which are serrated. This particular type ofknife has been found to be particularly eifective for extremely fastcutting of arapidly moving and tensioned web.

The shaft 30 rotatably supports the presser roll 40 which is adapted topress the web into contact with the adhesive A on the rolls R1 or R2, aswill more fully appear.

The knife is also swingable relative to this presser roll by means ofthe double-acting air rams 41 and 42' which are pivotally mounted at oneof their ends to their respective auxiliary arms 28 and 29 and at theirother ends to their respective arms 24, 25. Thus, actuation of the rams41 and 42 causes the knife to swing relative to the presser roll.

Another pair of double-acting pneumatically-operated rams 44 and 45 arepivotally connected at one of their ends to their respective arms 24, 25and are connected at their other ends to a cross shaft 46 by means ofeccentrics 47 secured thereto. Actuation of rams 44 and 45 cause theknife and presser roll to swing as a unit and move the latter during itsinitial or pre-set movement to a position closely adjacent the web asshown in Fig. 2.

Also secured at one end of the eccentric shaft 46 is an arm 49 which isswingable by a double-acting air cylinder 50 pivotally connected to thefree end of arm 49 and to the side wall 23. When the rams 44 and 45 havemoved the knife and presser roll assembly 17 "to the pre-set position ofFigure 2, ram 50 is then contracted to swing arm 49 downwardly, thuscausing shaft 46 and its eccentric 47 to rotate slightly and shift therams 44, 45 and assembly 17 as a unit. At the same time that ram 50 iscontracted, the rams 41, 42 are also contracted to swing the knifedownwardly relative to the presser roll and into cutting engagement withthe web. Stated-otherwise, simultaneous actuation of the ram 50 and rams41, 42 causes the roller 40 and knife 35 to move through their secondphase of movement, thereby urging the web into contact with the ad-'hesive on the web rolland simultaneously severing the a web. Means arecarried to the knife after the cut, the web might tend to bunch upbehind the knife and peel off from the adhesive on the new roll. It istherefore important that the newlyformed leading edge of the web befreed immediately from the knife. The means for clearing the web fromthe knife may take any suitable form, and a curved spring member 52 hasbeen shown as attached by cap screws 53 to the bar 32. The spring 52 isshaped so that its free edge lies closely adjacent the rear side of theblade. The tension of this steel spring is such that it will notrestrict the easy penetration of the blade through the web andwillcompress to the position shown in Figures 3 and 4 asthe bladeperforms the cut. Immediately upon the severance of the web, this springwiper means 52 returns to its normal unflexed position and in doing soacts to force the leading edge from the knife. The leading edge is thenfree to follow the roll R2 in its rotation, and is tucked under theincoming web under the presser roll.

As shown in Figure 3, the knife has reached the extent of its downwardtravel andit never comes into contact with theweb roll.. After the newweb roll is built by the knife to immediately iwipe. the newly-formed,leading edge of the web off theater- 1550 rated and notched knife, so asto insure that this new edge will follow the new roll and be woundtherearounds,

If the new edge of the web adhered even momentarily up on the roll R2 toa certain extent, say about one inch of thickness, the assembly 17 andmore particularly arm 24 have been raised sufliciently to release themanually operated spring-returned selector valve 60 mounted on the sidewall 22, and the function of the valve and also the pneumatic circuit ofFigure 7 for operating the air cylinders above-mentioned will now bedescribed.

A pair of manually operated and air-returned valves 61 and 62 (Figures 1and 7) are provided for actuation by the operator, thevalve 61 being thepre-set control valve which causes the assembly 17 to swing as a unitfrom the position shown in Figure 1 to that of Figure 2.

After this initial movement of assembly 17, the operator then pushesvalve 62 which causes simultaneous actuation of rams 50 and 41, 42 tomove the knife and presser roll through their second phase of operation,as above described.

The operation of the pneumatic circuit is as follows.

Air pressure is supplied via line 65 from a source (not shown) and isdirected via conduit 66 to the pre-set valve 61. When this valve 61 ispressed by the operator, air pressure passes through conduits 67, 68 and69 to extend the rams 44, 45 air being exhausted from the rod end ofthese rams via conduit 70 and out the exhaust E of valve 61. As theassembly 17 is thus lowered to the Figure 2 position, thespring-returned valve 60 is tripped by arm 24 and air is prevented frompassing through conduit 72. The air-operated valve 73 is blocked 'atthis time and air is thus prevented from passing via conduits 74, 75 and76 to the rod ends of cylinders 50, 41' and 42.

The operator then presses the operate control valve 62 and air pressurepasses via conduits 77 and 78 to shift the valve 73 and permit air to gosimultaneously to the rod end of cylinders 50 and 41, 42. The head endof thesecylinders are exhausted via conduits 80 and 81 to the exhaust Eof valve '73. As previously mentioned,

1 the presser roll is then held in contact with the roll being formedand when a suflicient amount of roll has been built up, the arm 24 islifted from valve 60 and the latter is moved by its spring to the normalposition. As a result, air pressure is permitted to pass via conduit 82to the air-operated valve 84 which also may receive air pressure via thepressure source conduit 85. Air from conduit 82 shifts valve 84 topermit air pressure to pass via conduit 86 to reset valves 61 and 62 tonormal. As a result, all of the air cylinder units and the valve 73return to normal, as illustrated in Figure 1.

Various conventional flow control valves 88 have been indicated inFigure 7 and they serve to regulate the flow' of airtherethrough. Inthis manner, for example, the speed of operation of ram may be adjustedby the flow control valves associated therewith.

By means of the present invention there has been provided a particularlyeffective cut-off knife and presser roll assembly that is brought intooperation in two stages, during the latter of which the knife and rollare simultaneously actuated to sever the web and press the new edge intoengagement with the new mandrel. After a predetermined amount of web hasbeen wound on the new roll, the various parts are automatically returnedto their starting position. A particularly efficient knife has beenprovided having means for insuring positive removal of the new leadingweb edge therefrom.

Various modes of carrying out the invention are contemplated as beingwithin the scope of the following claim particularly pointing out anddistinctly claimingthe subject matter which is regarded as theinvention.

I claim:

A cut-off knife and presser roll assembly for a continuous rewinder ofthe type having a moving tensioned web and an empty core adapted to bemoved adjacent i to said web, said assembly being swingably mounted,

said assembly including a presser roll adapted to press] said webagainst said core for adhesion thereto, mecha 5 niism for swinging saidassembly in a radial direction References Cited in the tile of thispatent re ative to said core between a position away from said web and aposition adjacent to said web where said pres- UNITED STATES PATENTSsure roll bears against the web, said assembly also in- ,973,515 TalbotSept. 11, 1934 cluding a knife which is swingable relative to anddirectly 5 2,5 2,90 Kwitek June 27, 1950 toward said core for severingsaid web simultaneously 2,5 8,069 Roper Aug. 8, 1950 with the pressingof the web against the core, said cut- 2,586,833 Kohier et a1 Feb. 26,1952 ting occurring on the discharge side of said presser roll 2,6 0,993Jeifrey Dec. 9, 1952 and as the knife moves directly radially towardsaid 2,686,015 Stevens Aug. 10, 1954 core, and a double-acting ramcarried by said assembly 10 2,689,095 McWhoxter Sept. 14, 1954 to shiftsaid knife into cutting engagement with said web. ,7 8,362 Piperoux eta1. Sept. 20, 1955

